REC was a Talmid of Reb Baruch Ber. Maybe his biggest Talmid. That is why he represented himself as an antithesis to a coexistensial approach to Torah and anything else. He is the author of the Divrei Eliyahu and was a Levi. Also referred to RESHC.
Reb SH was Rosh Yeshiva before Reb BBL ‘s son in law came to Torah Vodaas. That was non other than RRG who was from Minsk and a close associate of RAK.
Reb EK or Reb Luzi as he was affectionately known was a son of RUMK who was a RY in Torah Vodaas as well. He was Rov of the YILB .Also a major proponent of no CC.